Electrocum (Electro Stimulation); These are name for a TENS unit (Transcutaneous Electrical Nerve Stimulation) You will see these being sold in health spa and the like to help with muscle relaxation and muscle repair. They can also be used in sex play. The TENS unit fires and electric pulse into the body via a pair of electrodes. Electrodes can be placed any where one electrode at the base of the penis and one just under the glans penis.
There are urethal sounds. One can place the electrode on either side of the labia or place one electrode inside the vagina. You could place one electrode under the vagina and the other behind your lover's penis. Turn on the machine, set the strength and frequency and fuck fuck each others brains out.

E-Stims are sold on Ebay, Amazon, DHGate, Alibaba just to name a few sights.